On a basic level it's a story of a sixth generation application processor that is fabricated in a FinFET process. It's also a bigger story of Apple's semiconductor design ambitions.
Here we are. It is the sixth generation of Apple’s A-series Application Processor family: the A9.
The first generation A4 appeared in 2010. It was found to have considerable commonality with a comparable Samsung processor. Moving forward, the A6 showed us a custom Apple-designed CPU. This was, and still is, seen as no small feat.
The next-generation A7 moved the family into 64-bit computing. The A7 showed some interesting design decisions as there was no A7X. With the A7 Apple designed a single processor for the iPad Air and iPhone 5s even though these devices had a 4x difference in pixel counts. Further, the iPhone 5s now came with TouchID while the iPad Air did not.
From a manufacturing or fabrication perspective we have moved from the initial 45 nm process of the A4 to the 14 & 16 nm processes of the dual-sourced A9.
Apple A4 system-on-chip architecture (left) observed by infrared imaging through the backside of an intact die (click to enlarge). (Image courtesy of MuAnalysis.); Right: A9 die shot (Source: Chipworks).
At each generation of the A-series family there has been plenty of skepticism. There were those that said Apple should switch to Intel, switch to an Atom or switch to anything off-the-shelf. One RBC Capital Markets analyst even speculated that Intel might fabricate the A-series if Apple moved to Intel processors for the iPad. The real question though is whether the A-series processors and Apple’s semiconductor design efforts in general have set Apple on a path of differentiating its end products. This was Steve’s stated goal with the PA Semi acquisition. Interestingly, the other day a report had Google talking to semiconductor design houses about closer integration.
Do we already have the answer? It is time to look at the A9 in more detail.
Page 1: The road to A9
Page 2: What Apple said
Page 3: The die
Page 4: By the numbers
Page 5: Integration
Page 6: More details to come